1. Field of the Invention
The invention relates to methods and devices for ligament reconstruction in a joint. More particularly, the invention relates to a method and an implant to anatomically reconstruct the two bundles of the anterior cruciate ligament in a single femoral and tibial tunnel using a bone-patellar tendon-bone graft.
2. Description of the Related Art
There is a high prevalence of traumatic anterior cruciate ligament (ACL) injuries both in athletic and non-athletic population. ACL reconstruction is commonly performed to replace the injured ACL. However, osteoarthritis and knee pain have been reported among patients who had an ACL reconstruction surgery. (See, Aglietti et al. “Long term study of anterior cruciate ligament reconstruction for chronic instability using the central one-third patellar tendon and a lateral extraarticular tenodesis” Am J Sports Med. 1992; 20:38-45; Jomha et al., “Long-term osteoarthritic changes in anterior cruciate ligament reconstructed knees” Clin Orthop Relat Res. 1999; 188-193; and Pinczewski et al., “A five-year comparison of patellar tendon versus four-strand hamstring tendon autograft for arthroscopic reconstruction of the anterior cruciate ligament” Am J Sports Med. 2002; 30:523-536). Improving ACL reconstruction techniques that may restore normal knee stability and prevent joint degeneration remains a subject of continuing debate in sports medicine research.
Single bundle ACL reconstruction has been adopted by many surgeons. However, studies have shown that single bundle ACL reconstruction fails to restore tibial rotation to the intact level. (See, Georgoulis et al., “Tibial rotation is not restored after ACL reconstruction with a hamstring graft” Clin Orthop Relat Res. 2007; 454:89-94; and Ristanis et al. “Follow-up evaluation 2 years after ACL reconstruction with bone-patellar tendon-bone graft shows that excessive tibial rotation persists” Clin J Sport Med. 2006; 16:111-116). These observations are attributed to the limitation of single bundle ACL reconstruction to reproduce both the functional bundles (anteromedial (AM) and posterolateral (PL)) of the ACL. In order to address this issue, double tunnel-double bundle ACL reconstruction was introduced to reconstruct the two functional bundles of the ACL. There is no consensus among the studies in literature showing a significant advantage of this technique over the conventional single bundle ACL reconstruction. Although the double tunnel-double bundle ACL reconstruction technique is capable of reproducing the two functional bundles, it is a technically challenging procedure. The double tunnel-double bundle ACL reconstruction is also associated with an increase in the duration of surgery and higher cost as compared to the traditional single bundle ACL reconstruction. (See, Caborn et al., “Single femoral socket double-bundle anterior cruciate ligament reconstruction using tibialis anterior tendon: description of a new technique” Arthroscopy 2005; 21:1273; and Yasuda et al., “Anatomic reconstruction of the anteromedial and posterolateral bundles of the anterior cruciate ligament using hamstring tendon grafts” Arthroscopy 2004; 20:1015-1025). In addition, the double tunnel-double bundle ACL reconstruction makes a revision surgery difficult. By drilling two tunnels, there is an elevated risk of bone bridge damage due to an excessive loss of bone. These limitations in the current designs of the ACL reconstruction techniques leave a large scope for an improvement to this surgery.
Therefore, there is a need for improved methods and improved devices for anterior cruciate ligament reconstruction.